MINGACHEVIR, Azerbaijan -- The Mingachevir hydroelectric power plant, built in this western city in the years after World War II, got its start with the help of foreign labor: some 10,000 German prisoners of war were forced to take part in its construction.

More than 70 years later, the plant is once again relying on cheap foreign labor. This time, however, the workers are from China -- illegal migrants who say they are working and living in slave-like conditions.

The Mingachevir plant, set along the banks of the massive reservoir of the same name, is Azerbaijan's largest hydroelectric power plant. But as electricity consumption grows in this energy-rich country, the plant has sought to boost its capacity with a multimillion-dollar upgrade launched in 2008 -- with a rotating group of Chinese workers apparently providing round-the-clock, off-the-books labor.

Squalid Conditions

In the shadow of the heavily guarded Mingachevir plant, a dilapidated, three-story yellow building provides shelter for some 130 laborers, male and female, who say they are forbidden to leave the premises of the station for the length of their stay, which usually lasts between three and six months.

On a recent Sunday, the grounds appeared abandoned, with a lone Toyota Prado standing outside the building, which was riddled with cracks and broken windows. Inside, the stench of raw sewage was overwhelming. Down a corridor, one could hear the drone of a television, the angry buzz of houseflies, and the sound of snoring as some of the workers rested under thick mosquito netting before returning to work later that day.

The filthy conditions were amplified by the evident fear of the laborers. Reluctant to speak even in the presence of an interpreter, they revealed only a few details about their life at the plant. The Chinese are responsible for all the heavy labor involved in the plant's reconstruction, from masonry to stone work. They work every day, and often at odd hours, with one laborer saying the team had to be ready to report for duty as early as 3 a.m. They appeared terrified of being caught speaking to a journalist by their boss, a Chinese man who occupied the same building and who, in turn, reported to an Azerbaijani manager. But he did not appear.

Migrant workers are not a rarity in Azerbaijan, whose energy wealth has fueled a rapidly expanding economy. Many come from other former Soviet republics, particularly those in Central Asia, but others come from further afield.

Azerbaijani labor experts say officially, there is a quota limiting the number of foreign workers in the country to 9,000. (Azerbaijan's Labor Ministry says there are currently 9,163 licensed foreign workers in the country; of those, 595 are from China.) The country's labor migration law stipulates that all foreign workers must have official permission to work, and employers of foreign workers must pay a fee of more than $1,000 to the state.

Chinese workers are popular as they tend to accept lower salaries in Azerbaijan

Many observers acknowledge the actual number of foreign workers may be far higher, and that many migrants are hired by employers who deliberately seek to keep them off the radar despite the risk of steep fines if discovered.

Alovsat Aliyev, the head of the Azerbaijan Migration Center, a Baku-based NGO, says Chinese workers have become popular with many Azerbaijani employers because of their willingness to accept low salaries.

"If the State Migration Service finds out that any foreigner is working illegally and without a license, then the employer of that foreigner has to pay a fine of 30,000 manats [more than $38,000]. Employers have to assume responsibility for this illegal activity as well," Aliyev said.

The Chinese workers in Mingachevir did not say what they were being paid, although in other situations Chinese laborers have been found to earn less than one-third of local Azerbaijani workers, sometimes as little as $3-$4 a day.

'No Political Will'

The Azerbaijani Labor Ministry told RFE/RL that Azerenergy, the contractor responsible for the plant's reconstruction, had not applied for any job licenses for foreign workers. Nor was it clear whether Azerenergy, which is completing the construction with the help of a Chinese supplier, SNEEC, had asked the company to provide the labor. (Azerenergy declined a request to speak to RFE/RL.)

Aliyev said a delegation from the Azerbaijani Interior Ministry's department for fighting human trafficking traveled to Mingachevir to investigation the situation at the plant, but later said they had found only 37 Chinese, all lacking job permits but holding appropriate passports. But neither the Interior Ministry, the Labor Ministry, nor the State Migration Service appeared to be clear on who was responsible for dealing with issues related to illegal Chinese workers.

"All these governmental bodies are perfectly well informed" about unlicensed foreign workers, Aliyev said. "But there's no political will to ensure that employers who exploit illegal labor will be punished."

The demand for cheap foreign labor comes at a time when many Azerbaijani workers are themselves leaving the country to look for employment abroad. Some labor experts say laws governing the hiring of foreign labor are unrealistic because they focus on professional rather than blue-collar jobs, even as the influx of workers from China and elsewhere is rapidly unseating local laborers.

Sahib Mammadov, a labor-law expert, says officials have a poor understanding of the demands of the Azerbaijani labor market.

"Most of the jobs that foreigners are occupying should be given to Azerbaijanis. But we see in practice that workers from Southeast Asia are more attractive for local employers because of the lower salaries," Mammadov said.